Mating rates and their adaptive value in spiders of the genus Argiope

交配系统的特征是每个性别的交配伴侣的数量，而性别特异性交配率决定了性别内和性别之间的竞争，冲突和合作的程度。性食同类的蜘蛛物种与常见的系统不同，因为即使没有父亲的照顾，雄性也是一夫一妻制的。我的研究小组提出的一个理论模型表明，这种交配策略可以在非常特定的条件下进化，包括男性偏向的性别比例和一妻多夫制。一妻多夫制很难解释，因为女性通常不会通过接受多个伴侣和昂贵的交配来增加生殖产量。解释一妻多夫制演变的模型假定了直接、物质或间接的好处，例如，通过女性可能神秘地选择更好或更相容的男性。本建议的目的是量化的女性交配率在自然种群中的分布，并确定多个交配的成本和效益的性食人蜘蛛Ar$iope bruennichi在现场和实验室实验。我们将测量和控制直接利益，但将重点放在间接利益，通过后交配的可能性，以ry（神秘）的女性选择遗传上上级或更兼容的男性。神秘的配偶选择很少被证明，它的存在经常受到质疑。金蛛是理想的模型系统，因为雄性配对的精子转移器官一次使用一个，而雌性配对的精子储存器官，由于性相食，通常由不同的雄性填充。我们能够利用我们对几种金蛛生殖生物学的广泛知识，初步结果非常令人鼓舞。我们的研究将进一步了解雌性交配率的演变，并将是一个有价值的除了数量有限的交配后择偶的研究。

A mating system is characterised by the number of mating partners per sex whereas the sex specific mating rates determine the degree of competition, conflict and cooperation within and between the sexes. Sexually cannibalistic spider species diverge from common systems because males are monogamous even through there is no paternal care. A theoretical model produced in my group showed that such a mating strategy can evolve under very specific conditions, including a male biased sex-ratio and polyandry. Polyandry is difficult to explain because females will generally not increase their reproductive output through accepting multiple partners and costly copulations. Models that explain the evolution of polyandry postulate direct, material benefits or indirect benefits e.g. through the possibility for females to cryptically select better or more compatible males. Aim of this proposal is to quantify the distribution of female mating rates in natural populations and determine the costs and benefits of multiple mating in the sexually cannibalistic spider Ar$iope bruennichi in field and laboratory experiments. We will measure and control for direct benefits but will focus on the indirect benefit via the possibility of post - copula to ry (cryptic) female choice of genetically superior or more compatible males. Cryptic mate choice has only rarely been demonstrated and its existence is frequently questioned. Argiope spiders are ideal model systems because of the males paired sperm-transfer organs that are used one at a time and the females paired sperm storage organs that, as a result of sexual cannibalism, are most often filled by different males. We are able to capitalise on our extensive knowledge of the reproductive biology of several Argiope species and preliminary results are very encouraging. Our research will further our understanding of the evolution of female mating rates and will be a valuable addition to the limited number of studies of post-copulatory mate choice.